JEGS Vented AN Breather Fittings allow you to install an AN fitting into your valve cover, or other flat surface, without any welding. Simply drill the proper size hole and install. Can be used to connect to a vacuum pump, a crank case evacuation system, or other accessories. The special lock feature insures that the Vented AN Breather Fitting stays is place. The o-ring seal provides a leak-proof installation. Available in -10AN and -12AN fitting sizes. 1/pkg.